Structure of PDB 7qbd Chain A

Receptor sequence

>7qbdA (length=400) Species: 9606 (Homo sapiens)

EMCEIPEMDSHLVEKLGQHLLPWMDRLSLEHLNPSIYVGLRLSSLQAGTK
EDLYLHSLKLGYQQCLLGCQGKPSMGQLALYLLALRANCEFVRGHKGDRL
VSQLKWFLEDEKRAIGHDHKGHPHTSYYQYGLGILALCLHQKRVHDSVVD
KLLYAVEPFHQGHHSVDTAAMAGLAFTCLKRSNFNPGRRQRITMAIRTVQ
EEILKAQTPEGHFGNVYSTPLALQFLMTSPMRGAELGTACLKARVALLAS
LQDGAFQNALMISQLLPVLNHKTYIDLIFPDCLAPRVMLEPAAETIPQTQ
EIISVTLQVLSLLPPYRQSISVLAGSTVEDVLKKAHELGGFTYETQASLS
GPYLTSVMGKAAGEREFWQLLRDPNTPLLQGIADYRPKDGETIELRLVSW

3D structure

• PDB: 7qbd Generation of nanobodies targeting the human, transcobalamin-mediated vitamin B 12 uptake route.
• Chain: A
• Resolution: 4.18 Å

Interaction with ligand

Site #	Ligand	Ligand chain	Binding residues on receptor (original residue number in PDB)	Binding residues on receptor (residue number reindexed from 1)	Binding affinity
BS01	CNC	A	G85 Q86 Y137 Q138 D176 N224 Y226 M270 S357 L358 S359 G360 P361 Y362 L363 F376 W377 Q378 L379 L387 L388 G390 W409	G76 Q77 Y128 Q129 D167 N215 Y217 M261 S348 L349 S350 G351 P352 Y353 L354 F367 W368 Q369 L370 L378 L379 G381 W400
BS02	CA	A	Y226 Q266 N267 Q389	Y217 Q257 N258 Q380

Gene Ontology

Molecular Function

• GO:0005515 protein binding
• GO:0031419 cobalamin binding
• GO:0046872 metal ion binding
• GO:0140355 cargo receptor ligand activity

Biological Process

• GO:0006824 cobalt ion transport
• GO:0015889 cobalamin transport

Cellular Component

• GO:0005576 extracellular region
• GO:0005615 extracellular space
• GO:0005886 plasma membrane
• GO:0009897 external side of plasma membrane
• GO:0043202 lysosomal lumen

External links

• PDB: RCSB:7qbd, PDBe:7qbd, PDBj:7qbd
• PDBsum: 7qbd
• PubMed: 35218573
• UniProt: P20062|TCO2_HUMAN Transcobalamin-2 (Gene Name=TCN2)